I am getting ready to paint the 79 Microbus in Red below the waistline and White above.

I figure I should do the White first - but do I allow it to overspray on to the bottom half then mask and paint the red over?
Or do I mask the bottom half off as paint White, then mask the top half off as I paint Red?

I would like to get the seam between the two colours right...

White def first and no real point in masking bottom, Just overspray. Mask after to do the red.

either way it wont matter just get the tape straight

here is a tip my painter taught me... instead of using masking tape to mark the line use either normal sticky tape or use a good pinstripping tape, then you simply use masking tape to hold the paper and stick the edge of the masking tape on to the sticky/pinstriping tape. reason behind this........masking tape has a slightly feathered edge and the glue does not always cover the whole inside of the tape, this allows paint to bleed under the tape and it looks crap. the other way gives you a sharp edge. have fun

Red over white overspray MAY give you colour coverage problems

Get a drop sheet from Bunnings and use that as a mask over the lower sectuion of the car

And yes good advice on the 'two tape' method of masking - use oen peice of tape to determine your edge, then another to hold paper etc for masking... and ALWAYS use quality masking tape from a proper trade/automotive paint shop, cheap stuff tends to have furry edges, 'bonds' too quickly and is hard to remove OR it falls off

you can peel the tape after you spray it and it'll let the edge go softer instead of waitin after the paint hardens up to remove tape which leaves a harder edge. also if your good you can roll the maskin tape over to give it a soft edge when you spray it, but dont try this drinkin or the tape will be wavey lolol. dont pull the tape to hard or you'll stretch the tape and will set the straight line out of wack into two different ways. if your not careful with the type of grade of tape you choose, when you do pull it off it will take off the fresh paint you'd painted if you get a cheap hardware type tape instead of automotive tape..