UT2 exhaust valve stem seal?

Tried to transfer the valve seals from my BSP head over to my UT2 head and the exhaust valve stem seal dose not fit. It is not machined for it either. Do I not run one on the UT2 head?
O that's great. Ya the BSP had the same seal on both intake and exhaust. I decided to dismantle my BSP last night after all and put my 208 together. Well pretty much just test fitted parts as I could not find my lapping tool or feeler gauges last night. I have to pull it all back apart and check clearances on every thing. I checked putting an exhaust lash cap in intake last night and found out how much that changes valve train geometry. I see why you guys told me not to put lash cap on intake unless it was needed. I put the motor together 2 times because I put the piston in with the mark facing the wrong direction. Not sure if it matters but pulled it all back apart and faced the arrow at the pushrods like it was suppose to be. Need to recheck ring gap as I used 3 sheets of computer paper to check which I believe is around .009" but will recheck when I track down my feeler gauges.
I've only seen a few clone engines that ran a seal on both Int. and Exh. .....most just came with one on the Int. valve . But kinda of like Trinik said most people don't even use them on either.