Sand then fill and re-sand, or fill then sand ?

Started on bodywork on my Kelmark fiberglass kit car.

The previous paint appears to be a very low budge back yard job, possibly more than one. Rough spots (sprayed to dry?), smooth spots, high spots, runs, low spots (chips and deep scratches that were painted over) and that all to common fiberglass stress/spider cracks. All that said, it does appear to be a solid base if I get it smooth.

I have been taking down the high spots and runs, and often there is a low spot in the same area.

Should I be filling, then taking it all down to the correct level in one shot or continue with the take down the high spot, then fill the low and re-sand to the correct level?

Looking for the budget but OK way. Car is will never be worth enough to justify a total strip to gel coat and repaint.

Thanks

Disclaimer:  I'm not an expert by any means, but I have repainted a few cars and motorcycles...  My take is that you are likely to over-fill if you do it while you still have high spots.  I'd bring down all the high spots first.  If you're like me, you'll bring down the high spots too much, and would have to re-level anyway.

I don't know there's a way to shortcut the process.  

Without seeing it in person I'd recommend knocking all the high spots (using large sanding blocks) over a panel. Sand it down a little more than you think the high spots are.  Then skim coat the whole area with filler & block sand. If you do it this way you'll get less waves caused by the harder/softer filler vs gel coat or paint. You'll have a very thin coat of filler over the entire area.

I do have a suggestion while you're repainting. Remove the front park/turn signals and fill the openings. Replace the headlights with bulbs that have built in LED park/turn signals. Grills over light in pics below don't come with the headlight bulbs.

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In reply to NOT A TA :

Those lights are cool, but Every time I see them I think "that guy's blinker fluid is low."

Read this thread and do what he did.

https://grassrootsmotorsports.com/forum/build-projects-and-project-cars/neon-acr-coupe-2012-challengedd-build/50461/page27/

I would declare some point before you sanded into the weave to be the "high point" where you dont want to sand beyond unless you are going to re-gell coat.

If you hit the glass it's going to be less fun. Do what you can to not get into the glass. If you have the patience sand>fill>sand>fill....

AngryCorvair (Forum Supporter) said:

In reply to NOT A TA :

Those lights are cool, but Every time I see them I think "that guy's blinker fluid is low."

Where's synthetic blinker fluid? ahaha  During the day they look like normal headlights from more than a couple feet away unless the blinker or park lights are turned on.

When I saw the GT in IRRS's garage I thought it would look good without the front park/turn lights. I just googled Kelmark GT to look at pics of done cars and there's a couple pics of one in the 3rd row down at this link without them. So apparently someone else thought the same as I did. https://www.bing.com/images/search?q=kelmark+gt&qpvt=kelmark+gt&FORM=IGRE

I have removed the kelmark glass front bumper, that where the body work started a little earlier then planned. The plan was to loose the kelmark blinkers also and do more of a pseudo p...... 9o iv (dont want my car confiscated) look. 

Just messin a round with the 2 hole bezel. 10 points if you can guess what it's from.