Other than Pearl Jam, I am not familiar with any of those bands. But I would still have to say that you are looking at the wrong amp.  A MV on a TW clone is kind of like installing a smog pump on a 1969 Camaro. I think you already identified the better amp for you. Either a 2203 or the 2204 would be fantastic. They are both available with a PPIMV. Just send Ceriatone an email, Nik will be able to help you much better than me.
Good Luck

Did you ask Ceriatone?   It would all depend on what you wanted them to do. Other than some different spec trannies I am not sure that I would want to mod a TW clone. Unless you know something that the rest of us don't.....
What did you have in mind?

Good job! 
Those jewel lights are easier to deal with and they come in all of those different colors too.
What kind of amp was it?

Wow!!!
Looks like somebody did a nice job with the Tweed. And a real Pine cabinet also. What brand power tubes are those?

Hhmmmmm.   The toggle switch to disconnect the PPIMV is new to me. I am not any kind of tech, but I don't understand what a toggle switch can do. All of the wires and the dual stack pot are in there. Turn it all the way to the right and it is "off" I thought.
How much further out does the toggle take it, back to the board maybe?  I just pulled a PPIMV out of a plexi lead/converted to bass. Maybe with the Mod you are talking about I could have left everything in there?
Thank You

Hhhmmmmmmm.... Now I have to ask a stupid question. Does the  JTM-45 have six bolts?  Most chassis' have four. Anyway, I would think that you will want large, flat, washers on the bottom of the cab to help distribute the load.
Six you say???  I am no Marshall expert, that.'s for sure. But I would think any cab maker familiar with amplifiers will have a quick answer for you. Have you tried all the usual places?  Metro, Mojo, and all of the other DIY guys.
Good Luck

We do not have the best camera in the world... Did some minor changes, including an Alessandro volume pot. For the most part it is just an off the shelf Ceriatone.

Holy Cow!!
Too bad about that, looks like it really took a shot. I just went through a damage claim with FedEx. They were actually very up-front about everything, and wrote me a check pretty quick.
Hope you keep us up to date with what happens. I bought a Tweed Deluxe from Nik that was built wrong. I took some pictures for him and he was real good about doing the right thing. Not that this was the fault of Ceriatone. But like I said, hope you keep us in the loop regarding your amp.
Good Luck

OK Guys!
Thanks for your overwhelming replies. :  I am now ready to make the changes. Looked over the layout a few times, noted the component differences, and I ordered the parts. I'm sure it will take me several days, but the tone switch should be nice.
I am also having a new faceplate made that will better incorporate the MV. We actually have two of these, should have had Nik do this when we placed the order.
Go Ceriatone. 

Hey -
I am in the USA and have never had to pay any type of tariff, duty, fee, customs charge, etc. etc. etc. I never bought a kit, I have 5-6 finished amps in a cabinet. Never any surprise charges or fees. 

What components do I need to change to make the change from lead to bass. Guess I could compare the two layouts, or is there more to it than that?  So... what do I need to do?
Thank You

Was wondering what you guys were using for tubes and speakers. Are these Expression Amps anymore sensitive to tubes than a Fender or Marshall?  We played ours for the first time. And when we got the volume past half way things got bad. No more gain or volume. The tone gets muddy and there is a kind of high pitched, swirly kind of noise. Have never really heard this before. Not a micro phonic tube, it is much different than that. I guess oscillation is a possibility. But the lead dress and workmanship on this amp seem so well done that I do not think that could be it. I suppose preamp tubes would be the easiest place to start. Perhaps I will just go through them one by one. Any of you other guys hear this when you get your Expression opened up?
Thank You

I guess this could start to get ridiculous, but are they really all that different? It would indeed be awesome to own a brand new, hand wired, all tube, integrated stereo amp. 40 watts per side would be just fine.
Thank You

How about a dedicated bass head like the Mesa 400 or the old Ampeg SVT?  I am just dying to get my hands on a good quality, new or almost new, hand wired, tube head for bass. What do you guys think, anybody else interested?  Any other suggestions in addition to the two amps that I have listed?
Thank You

Miracle Man -
There is plenty of overdrive in that amp. I think you would be sorry if you dropped a 12AX7 in that amp. It would have no headroom what so ever. Just listen to Larry Carlton on Steely Dan's The Royal Scam. His lead tone just plain screams. No pedals, just him plugged straight in. Take a look at his website (I think it is mr335.com or something like that). There is a video with him showing you exactly how to get that heavenly lead tone from a Tweed Deluxe. You will be glad you checked it out. The only short fall of that amp IMO is that it is just on the border of being a gigable amp if there is no PA. I have one of Nik's 5E3 amps and I can vouch for it whole heartedly.