Doing a 24v conversion into a Saff, using the 24v granada radiator, got some twincam 8v Sierra fans and cowling but they won't fit!

No clearance between the back of the fan and the pully's on the BOA.

I thought everyone used them?

Ken lowe fan kit too expensivo, scared of cheap E-bay slimline fans, tried some from a v6 vectra too, but no joy...

Help please

Cheers