Forget it.
You will not be able to pass a multi engined Instrument Rating Test with just a PPL, 10hrs Multi and the compulsory IR module.
The CAA testing unit would not like it either. The IRT is the first time the CAA actually gets to fly and test you. It is regarded as the final tick that will allow you to take unsuspecting ticket holding punters into the air.
For this reason the test is regarded as the last line of defence for the general public.
They can and will fail you even though you managed to keep the aircraft within the set tolerances for the whole flight. They are looking for Captaincy. Basically they can ask themselves would they be happy sending their kids up with you as pilot. If the answer is no they will fail you. With <100hrs TT and very very little solo I suspect you would fail the kids in the back test.
Undertaking the mandatory IR course with very very low hours is likely to lead to a few hours extra training required.
Such extra training is charged at the rate of c. £350 an hr. Therefore it is false economy to try to save cheap hour building hours at c. £50 an hr by doing an IR as hour building and needing an extra 5 hours due to you diminished experience.
There are few shortcuts in this business.
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