240sx vet NEED HELP ASAP! question on purchase "lifter cup rattle"?

[abc123omg]

Hey guys,

I have been away from nico for a while but im hoping to be back here again.

I found this 1990 240 with a KA24E and the owner claims that even though the "lifter cups rattle, it does not affect the motor at all". he claims they are "seals around the lifters"

what exactly is this "lifter cup rattle" and does it really not affect this motor at all? aside from the rattle, the car has a new radiator, clutch, slave cylinder, and recent full tune up of plugs, wires, and oil change.

a few dings on the exterior and interior has a cracked dash (normal i guess) and a digital gauge cluster that works every now and then...(is it possible to just plug in an analog one?). He also said the AC stopped working because the light wont turn on when anymore. He claims this is due to the big fuse under the hood.

I plan on trading my 96 maxima for this. Any insight on the AC, lifter cup rattle, and gauge cluster?

Ive been searching for info but i really need to get info asap and get this deal done with. Thanks!