Hello Tom, welcome to this forum!
cheers for the compliments on my car, i can basically scetch out for you what needs to be done for a 200bhp engine in a RHD car
lets start with the clutch. i currently run lower boost than the setup is made for because the strengthened sinterplate clutch doesn't hold, my new plan was to bolt a renault 5GTT flywheel on with strengthened pressureplate and then again the sinterplate that fits the V340 spline pattern. that should hold to about 400/450Nm
biggest problem with this is that the starter teeth on the flywheel are on a different place compared to the 340's flywheel but a adaptorplate for the starter will solve that. then there's the smaller problem that the TDC sensor on the bellhousing is also on the wrong height (and i also believe that the TDC sensor on the r5's gearbox is straight up; TDC sensor in the volvo is about 20degr to the lh-side so another thing to account for though i personally thought that's nothing a custom bracket or trigger wheel on the crankshaftpulley wouldn't solve.)
then there's the exhaust; standard and uprated manifold's that fit the R5 are useless as they place the turbo behind the engine and there really is no place for it there. a custom exhaust manifold is the way to go; but this will be one of the most difficult things of the entire build due to the RHD, it is definatly worth while to get that right as a proper manifold definatly benefits the turbospool
wiring it's very simple, everything that's 340 can be used. just make sure you route the 2 wires to the starter different, so they don't melt from the exhaust pipework
on a very important notice you do have to swap the entire Renix unit for a R5GTT one (code 208 or 209) as a std B14.4 Renix isn't made with a boost-curve so you can potentially blow the engine to pieces. you can also bolt on a knock-detector from a phase2 R5TT and wire this to the renix aswell; that also saves you quite a bit of work!
i personally find a rev-limiter a big must for this engine as when i drive in the wet and when it starts to slip it'll rev to the limiter at 6500rpm in the blink of an eye. also i personally prefer to use the 340 front end of the B14, so B14 waterpump, alternator, brackets and pulley's. you will also have to make new engine mounts as a B14-T will rip any original mount to pieces in no-time
i might have forgotten some things but the most imporant bits are here, i frequently look here on this forum so feel free to ask
oh and my own B14-T is/should be making about 200bhp atm though i never dynoed it (tuned it to 1,1bar on my own AFR and EGT gauges; will dyno it after the injection-conversion is done) compared to other cars with likewise power it should be there, i can keep up with my mates STI Impreza and a standard B14 won't get you there

i'm allways curious for a speclist on the engine he's build; got any pics/more info on that?