Does anybody have a link to the complete procedure for adjusting timing?

My timing chain is spot on, my IP has new delivery valve o-rings and pressure valve seals and my mpg is going down.

I know that it's really hot, my A/C is working it's tail off and one of my auxiliary fans has stopped working, but I expect better than 25 mpg in almost all highway driving.

I must also say that I drive in a very hilly and very windy part of the world but if some posters on here are telling the truth about their MPG(38.4?, 30/31 in mixed driving?) I am getting hosed.

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1993 W124 300D
-297K on the clock as I type this.