Turbo upgrade questions - rhd '85 CQ (long)

[Duncan Thomson]

A local guy has approached me about slapping a turbo onto my KV engined
coupe quattro.
He says he's done two similar jobs, and they were very easy. He suggested
keeping the block the same, and swapping the pistons for the lower
compression ones from the turbo, along with swapping over the turbo, IM,
EM, and intercooler.
I don't know the engine model, but it's apparently from a 200T, and he owns
the complete car.

two questions pop to mind:
1) Moving the battery to the boot was suggested to give more room for the
turbo setup, but it occurred to me later that my battery is on the right
hand side (looking into engine bay), with the brake booster on the right...
Is the brake booster going to interfere with any of the turbo gear? can I
move it? replace it with a part off a different car...

2) Is this as easy as he makes it sound? He's a nice guy, and sounds keen
to either do it for me or to provide assistance, but I doubt it is as easy
as he suggests. Especially since he doesn't even know what engine I have,
and is suggesting a piston swap from another car, which he couldn't
remember the model of...
(he thought a WC or something..?)

Would this be recommended anyway, or would you guys suggest the full engine
conversion..?
I seem to remember people suggesting the full swap was preferable, and
figured this was the only REAL option... but this guy insists that it is
really so easy...

thanks for any input / opinions...

Duncan

p.s. he gave me my first ride / drive in a turbo audi (200TQ), apparently
it's not making much boost at the moment, but sure pulls a lot stronger
than my poor little CQ...
enough to make me yearn for a little more power to go with my suspension
upgrades...