Update - I ordered a long torx screwdriver set from ebay opened up the mac se and gave it a good clean. I washed the motherboard under the tap and dried it, changed the CMOS battery which was not soldered fortunately, and thoroughly cleaned the floppy drive with ear buds and white spirit. I also gave the monitor tube a good clean with kitchen wipes after waiting days for it to discharge. It now boots up fine on the floppy drive. The floppy drive was full of fluff and dust. Unfortunately the hard drive will not boot. It is an Apple Miniscribe 20 MB original. I managed to obtain the maintenance guide and from the yellow LED flashes was able to diagnose - it cant find track zero. Apple HD SC setup does not find it, saying it cant read the required information. Will Lido or any other tool format it even if it cant find track zero? Unsure why it cant create a new track zero. I just need to find a cheap 20MB SCSI replacement drive on ebay UK.

Interesting finds: Two of the three ROMs were slightly different to that advised in the service manual. 341-0701 and 341-0702 instead of 342-0701 and 342-0702. Must be an earlier version ROM set for the MAC SE FDHD. It seems to read 1.4MB floppies and work OK anyway.

I was trying to transfer the lido SCSI format tool to a PC floppy to try it on the SE. Can some one advise what the file extensions SIT and SEA mean? I think a SIT file are an archive but how do I transfer it onto a Mac floopy I have created using WinImage - do I need to use transMAC?