Good to hear that you're not intimidated by this repair. Sure sounds like you will probably get by with a valve job. I doubt anything you did contributed to the demise of the valve unless it was adjusted wrong. Exhaust valves normally get beat up more than intakes. Might be a little premature, but if this car lived life in the city (low overall mileage but many run cycles) I wouldn't be surprised about valve wear.

Along with what John Mc said
Rocker Arm - I usually back the valve adjusting screws out to relieve some of the pressure on the arm before removing the arm bolts.

Heater pipes - Yes remove the upper hose. I don't think you will have to remove the lower one. Definately drain both block and radiator, otherwise you will spill coolant into the cylinders when removing the head. You will probably spill some, but this will reduce the amount...dry it well after removing the head.

Temp sender - Keep a close eye on it when removing. Don't let the capilary tube twist with the retaining nut. If it does, soak it again with PB and be patient. All bets are off then!

Linkages - I pull the linkage at the carbs and then remove the linkage from the firewall to the intake to get it out of the way. Comes apart real easy. I pull the carbs also at this time.

Manifold to downpipe connection - Good luck. Soak it and cross your fingers. Be sure your wrench fits tight and you can get a straight pull on it. Don't use an open end wrench...box or socket only. You don't want to round off those nuts obviously. It may be possible, but a pain in the neck to leave it connected and remove all the manifold to head nuts and pull the manifold out of the way. Sometimes the studs don't give you enough room to pull away though.

This project is straightforward and you've got the right attitude. Go for it!

You have a torque wrench for re-assemby right?


--
'60 544, '68 220S, '70 145S, '72 144E, '86 745T