Traynor PS600

So a friend of mine dropped off some amps to be repaired and basically abandoned a Traynor PS600 for me to play around with. Initially I was uninterested but I have become rather intrigued and would like to get it working just for the heck of it. (Following image from the web as mine is in pieces)
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Inside the amp there is a crowbar circuit with a particular bit of nastiness,
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In the upper left corner labelled R53 is a long piece of nichrome covered on both sides of the board with asbestos tubes.
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I want to get rid of the asbestos and the nichrome, does anybody see any problem with replacing the nichrome with an MOV or should I opt for a .5 ohm power resistor? I'm not a fan of shorting Vcc without a fuse to protect the secondary windings.
Vcc is +/-65v in high range and +/- 55v in the low range and the primary is protected by a 12A fuse, no fuse on the secondary side of the power supply.