Pleased with my recent purchase of a 91 MR2 5S-FE N/A. The car is in sweet shape with original paint, no rust other than two little tiny spots that need doing. Underneath is as clean as the top side and there is virtually no wear on the seats.
I do have a few questions. 1st rustproofing. I took out the trunk liner and see a light oil was sprayed into the pockets on either side of the rear trunk. I haven't seen this anywhere else including underneath. What product do you recommend using for rustproofing. My thought was to do it myself.
Also I will be parking the car over the winter! I plan to drive it next summer and fall then get it painted the following spring. Will rustproofing have any kind of negitive effect on having the car painted? Is it ok to get it on the boots any rubber mounts or seals?
Next the engine, which was compression checked before I bought and passed with flying colors between 201 and 205 across the top with 153,000 miles on it

Should I consider changing over to synthetic oil. Is there an advantage, improved engine life? or should I just leave well enough alone. What oil should I use for over the winter SAE 30 or 10w30? Other then move the car a little around from it's parking spot in winter, I won't be able to get acces to take it on the road for a real run between Dec 1 and March 15.
Also under the car at the back, bottom of the fire wall there are two what appear to be mounts for a shield. They are sort of angled z shaped straps of metal that come out from the bottom of the firewall, about two and half feet apart. I'm guessing maybe a shield was attached to them that then went across to the bottom of the engine area. Not the shields on the firewall itself, this looks like maybe one ran flat horizontal like it would have been flat with the road and possibly to protect the bottom of the engine area from road debrie.
Now the rubber door seals, truck, front, rear and moonroof are all in excellent shape. As is the dash. Nothing leaks and I'm wondering what I should use to keep the rubber seals and dash material in good shape.
Really appreciate any help you might give. Sorry if they are silly questions but I don't want to mess up a good thing by stupidly doing the wrong thing lol. And well you guys have the experience with the car so who better to ask

Thanks again, Cheers Nova ~
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