Why press your luck?
Do all four upper guides (replace the liner on the tensioner unit as it's super cheap), chain, tensioner, cam oilers, plugs, wires, cap, rotor... then you're done with it for a long, long time.
PO of my 560 did it, I had no records... but when I popped the valve covers and saw white guides + an IWIS chain I was pleased. They just skipped the cam oilers so I swapped them too.
Maybe you can find a garage local or know someone that will let you use their space for a weekend to replace it all?