A very warm welcome to the forum DavidR
Personally, I would not worry too much about the dirty Pinto engine .... Good strong engines but didn't have the best of rocker cover gasket's.
That said, they usually stay dry untill the rocker cover gets a tad over tightend
Your build budget will help you decide if you keep the standard engine set up or not.
If your budget is tight or you prefer to spend extra money in other areas .... Keep the engine as is.
If you feel that you need a performance boost from the engine ..... There's plenty of options to choose from .... at a cost !!
Which ever way you decide to go, all the help you need will be found here.
Enjoy your build