i thought that they sat pretty close to the firewall , i suppose i could always cut it out and weld some sort of boxy type thing to gain some clearance(like they do on old mini's when fitting webbers, as far as the gearbox go's the only difference that i know between pulsar sr20's and s14 ones is the block construction in that the pulsar block is all alloy , i can't see why they would cast a different block for just one engine type surely it would'nt be cost effective, but then again i could be wrong