I've not done this myself but have spoken to a Pascal from the Dutch MonoConnection that has successfully done this conversion.
My understanding is
- The engine mounts line up but you may need to bush the upper rear one.
- The electrics are completely different, the easiest approach would probabaly be an SZR/Muz Skorpion/XTZ harness, complete with CDI, reg/rec etc.
- Carbs are further apart so you will need SZR/XTZ items and wont fit airbox.
- The SRX oil tank will be in the way of the starter motor, SRX600 monoshock or SZR oil tank should work, (Pascal modified his)
- Chain alignment, the sprocket extends 10mm further out than the SRX, this cause wheel alignment and issues and the chain runs very close to the frame, apparently the XT600 has a dished front sprocket which can be reversed, the bolts holding the seal retainer will also need machining
- the right hand downtube will need to be modified to clear the water pump
- mechanical rev counter drive will need to be fitted to head if you want to keep the SRX clocks.
- Exhaust - not sure I think Pascal modified an SRX exhaust to fit.
- Need to find space for a radiator/thermostat

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