I don't know of anyone who's done it. It's been asked before and it is not a bolt in. Even if you fabricated mounts, you still have to worry about precise placement of the engine in order to make one of the belts work properly.
IMO:
I have a ported/piped 600 + 700 SX + a ported SRX and, from experience, you don't need the SRX engine in the SXR chassis...those Red Heads can be made very powerful + reliable[close enough to an SRX engine] and No Power Valves to adjust + clean.
JM.02c
Ok
So I already use Turk's clutch set up
Reed notch is done
I have 8200kms on it now, so I will do new pistons and rings before next season.
I am only going to take one lawer off the head gasket due to the potential of shitty gas.
Should I do a boost bottle?
Who can suggest a brand of pipes and where should I send my heads to get ported?
I put pipes on my sx 700 and then took them off a week later because I didn't like them. It just about cut the fuel mileage in half and didn't run right in all temps without changing jets like stock did.
The power was very nice though, it would pull really hard. The srx engine would be nice to have since it has all the power but still has excellent reliability and fuel mileage. But it sounds like a good amount of work to get it in there.
port the head? It's not a 4 stroke! you will need some cylinder and case porting. Redheads are very easy to pipe and very reliable when you get the jetting down. Find a set of Bender, Power Inc,Hauck, or SLP pipes slap them on and get some case porting with SRX/Viper reeds and you will be right with SRX if not more power.
I had a 2000 SXr with Bender Triple pipes, center layer of the head gasket removed, boost bottle, reeds and the clutching. It was a very fast sled and could keep up with a stock SRX.
Kewl. If your looking for more power after you've done all the above mentioned, you could look into a small shot of nitrous as well. It won't hurt anything if kept small, but will give you that extra bite when you need it. I was going to do it to my sled, but I bought the 4 stroke. Hell, I still may do it on top of the supercharger! lol But that's just me, I am a bit "off"! LOL