grid heater works well in those, but you may have to slave it off something to get enough amps depending on your battery health.
good luck.
beater XJ didn't really want to fire this morning, but after a second it caught.
oil pressure took a disconcerting amount of time to come up. No knocking noises though.
If it wasn't for the serious ring leakage I'd swear this thing had a new bottom end. When I drained the oil last week it reeked of gas, so I guess it really is a 257K mile motor. Of course that oil may have been in there forever to. Who knows.