yikes, I seriously doubt ANYONE needs the full unleashed power of a 100w plexi - I'm a loud player and rarely get mine past 3 or 4.
those JTM45 reissues through a 4x12 with RI greenbacks won't really give you much 'cut' (having played such a rig).
here's a cheaper option that will give you the desired volume increase but come in cheaper.
(1) get rid of the RI greenbacks and replace them with G12H-30s. the 3dB increase in sensitivity means that they'll be noticeably louder than the G12Ms. you should easily be able to get £100 for the four G12Ms and four new G12H-30s will set you back £200 from
www.loudspeaker.co.uk (ok, so we've spent £100 already)
(2) replace the output transformer with a 50w plexi type - your PT should be fine since you're still gonna be using the same valves (2x 6L6 and 3x ECC83, I'd dump the GZ34 in favour of sicilon rectifiers or a Weber Copper Cap). a decent 50w OT is gonna set you back around $150 - by the time you have postage and import duty, say £125 for the OT. if you can sell your old JTM45 OT on ebay for £25 you've only laid out £100.
so, for a total outlay of £200 you've just made a MASSIVE improvement to your amp rig. you could leave out the speakers and you're only spending £100.
:twisted: