fitting a phase 2 sump and windage tray to a phase 3 zetec. on the phase 2 the tray fits on double ended main bolts, the 3 is an intermediate sump.

I have the tray and bolts, but, the main caps on the phase 2 are 20mm deeper, hence the bolts are 20mm too long, my thought is to turn up 4 spacers 20mm long to fit under the heads of the 4 bolts. Spacers will be under compression not stretch forces, so I don't see a problem.
Anyone forsee any probs?
Cheers.
Pete.