Any frankenrovers out there?

I'm looking for a new water pump for my '83 RRC. After some research, the engine looks like it has the induction off of an SD1/3500NAS, but the block/timing cover appears to be '83. I've got the parts numbers for the pumps that fit this engine, but I need a newer-style hub (3 bolts for the pulleys, threaded end for the viscous fan clutch).
Does anybody know if the newer style pump (STC 483) would cross-reference with the older styles (e.g. RTC6335, RTC6331, RTC3660, or RTC6336)? The pump bodies have the same mounting pattern, but AB informed me that eventhough the body and pattern look the same, they may not/will not be compatible...true? Anybody know where to find just the hub (or the p/n) that mounts to the pump shaft? (still trying to contact Big Sky and Rovers West but nobody's home...)

I dunno if I'm a moron...or if AB is...

supposedly the timing/front cover for the RRC is the same p/n, 3.5 thru 3.9 carbed or FI. If the cover is the same, then any pump should be cross-compatible. Anybody want to share some conflicting evidence before I order a new pump...?

Wow,

Two bits of cheap B@stard knowlege to pass on in the same day. I was faced with a similar prediciment 2 weeks ago. The pump on my 1990 RR was leaking, and Iwas going to try to put the 1980 RR pump to get by for a while. Well sure enough the old pump would go right on the newer engine, same bolt patern, same gasket. Where I had issue was with the pullies being in different locations, I ended up buying a new pump from BP for $105, and that included the gasket.

So in answer to your question, they will bolt up directly, and it sounds like you already have the later style with the fan clutchso Id give it a shot.

-Jeff

Cheap bastard info? LOL! I guess I was the cheap bastard for buying this RRC with the frankenengine!

I'm now kinda pissed at AB: "They changed pumps so many times over the years...yeah, it may look like it bolts on, but it won't work."

Won't work to means it won't pump water because of some design change between the pump and front/timing cover. Mismatch of pulleys...I can fix that.
I took a gander at BP's site and saw that the timing cover for the grey-market RRCs and the 87-94 RRC were the same p/n. It's a shame AB doesn't have this info...maybe they are hiring Autozone flunkies (...uh, it's not in the computer...sorry). I'm callin' BP tomorrow for my pump!

I have also run into this problem when removing parts from donor engines and trying to fit them on others. I have found, there are a few variants, and the biggest impediment I have found is the physical size of the water pump as it relates to whether the engine is serpentine belted or uses multiple V-belts. If you look at the left side of the engine, you will notice that the water pumps (and front covers) of the multi-V belt engines extend further to the left than those fitted with Serpentine belts-the power steering pumps were changed at this time also, although some have told me the old style power steering pump can be fitted although subsequent investigation proved that some heroics with plumbing would be required as the serpentine engine mount is completely different.

Hope I added something of benefit and didn't further muddy wurky water.

Paul