redtop...no. XE...yes!
the main things to look for with an XE conversion...it make sure its right. Check the engine sits level. Alot of people get it wrong and kill XE's because they are on the piss and the oil doesnt transfer properly, as well as a host of other things. So check the mounts.
Another thing is the gear linkage. CHeck how they have done it. M-tech do a shortened linkage specially for the 2.0 conversion (about £70) and its well worth it. Normally people have bodged it by bending the std one, and that again, just means you kill the box in the long-term! If it works at first whn you get it, then okay...but i would suggest investing in the m-tech one tbh!
Chassis strengthening should have been carried out on the front crossmember, so check that has been done, and all the welds are in good condition.
Make sure the brakes have been uprated. You want to be checking that 2.0 brakes have been put on, as a 1.4 setup will not stop you quick enough!! As well as this, check the suspension set-up is decent...theres alot of weight in that engine!
Engine health is normally good on these engines as they are brilliant units. However, keep an ear out for any obvious head wear noises. They arent normally noisy engines, so if there is an obvious noisiness there...you may want to ask questions. Also, when they start it...stand at the back and look for smoke. Also, once its warm...ask them to rev it a bit and check again for smoke. Most of these engines are about 15 years old, so most now are looking at rebuild or refresh territory. Remember that the very nature of the car/engine means it will have had a hard life in that car...so just check everything over, and ask him how often he has been changing the oil and generally servicing it (i change my oil every 2-3k).
Lastly, check the documents and make sure it is registered right. You dont want to be getting pulled by VOSA and getting the car taken off you. They are wising up to this conversion now, as are the police...so if it isnt...get an engineers report from a garage and get the V5 submitted with the changes...otherwise all sorts of nasties can come down on you.
That should do you.
Of course you still need to be looking to for the usual corsa problems, rust on the chassis legs and the condition of the front crossmember etc...but make sure the engine conversion has been done proper. its not just a case of lobbing the engine in...it took me a month to get everything prepped right to do mine, and that was with the car off the road. Some people just go " yea i chucked it in, in a day!" and they just dont do it right.
Be careful...but there are some superb examples out there!
. Although the engines last a long time 90k is still a lot considering its probably been thrashed. Also if you plan on using the backseats look at the suspension and wheel set-up. Many redtops have been lowered so much that they cannot have rear passengers without the wheels rubbing so its worth having a check on that. Those are my tips anyway, happy hunting m8 