I'd say running and MOT'd would get you the best "value" return as long as you do the work getting it running and MOT'd and presuming it does just need a top end.
I'd doubt you'd see an increase in value to match the cost involved in either a full stripdown or just a paintjob.
You might see your money back and a fair bit more if you replace the bodywork with Hong Kong plastics presuming you get a good set, I've see some lovely ones and some real dogs.
There are some dealers asking some big money but I've seen precious little evidence of private sales coming anywhere near those levels.
Then again, if you want a fast few quid PM with a price, I may be interested
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