Fixing someone else's mistake aka help!

I'm in a bit of a sticky situation with my T5 as it was (past tense) having a manual gearbox and new engine fitted by someone who has since given up.

I'm left with a car that has had half a job done (new engine and manual box fitted) but the rest is a relative unknown.

I've already had the wiring sorted by an auto electrician but I'm struggling to find someone to finish the job, if that's even feasible at this stage.

Apart from Tim Williams, who else might be capable and willing to take on this sort of job?

If I can't get it finished I'm probably going to have to cut my losses and either part out or sell the whole car, which makes me sad.

What's left to do?

The remainder is:

Re-fit the new pedals and gearstick along with the interior that had to come out originally.
Reconnect all the piping and wiring in the engine bay (which seems to be the main headache)
Fill with fluids etc and make sure it runs after all that