Is it possible to upgrade to 2 sided keys?

Tried searching, no results. I have an 88 XJ with worn out locks on the doors and a sloppy ignition lock cyl. and I was wondering if it was possible to change the locks to the 91+ two sided keys.

Yes. IIRC, the GM-style column was used until 1996 with Chrysler double-cut keys, so it's essentially a matter of changing out four lock cylinders (two doors, liftgate, and steering column.) You may have to buy the locks from a parts house and have them rekeyed by a locksmith, or just order them from a 'smith, but if you get the locks separately you can just drop them off for rekeying.

You may also be able to order a full set cut to one key, depending on sources.

Thanks 5-90. I have yet to find a source with a whole set keyed the same so I will probably just go with your suggestion of having them rekeyed.