A lot of Carello spotlights have popped up recently on Ebay. One pair with 1x in good condition and the other had rust in the reflector and missing the rim. But good lens and good body. I snaffled them for $100pr compared to $900 for a NOS and $400 for some nice used ones.
Then this morning a Carello 591 popped up and was able to grab that for $50
The 457 and 591 are almost identical aside from the part numbers in the lens and the 591 body has an off-centre tab for the screw and clamp.
Now I needed to understand how to remove the lens from the reflector so I could switch lenses, ending up with the 457 lens on the 591 reflector and that being fitted back into the 457 body. BTW the reflectors are the same part number.
A quick google and the method is to put in the oven at 130deg C for 15 mins then pry lens away from the reflector. Very glad to say this went smoothly. I'll do the same to the 591 when it arrives and should end up with a very presentable pair of original spotlights. I will also need to order a roll of Butyl rubber glue/ sealant to fix the lens in place.
Interesting to note the 591 was fitted to MK2 Mexico in the UK. Whereas Rally Pack got the 457.
Last two pics are the 591