When I built mine (JD4300) I wanted to have the forks at a slight angle up when the FEL was all the way down so I could get logs to roll to the rear of the forks. I could always curl down if I wanted them level to lift a skid, but even curled up I couldn't get enough tilt to them to do what I wanted if the FEL was all the way down.
The way mine is built the forks and back frame are about 75 degrees instead of 90. Had I been thinking ahead I would have done it different somehow but I would still want to be able to rock back on those forks for picking logs off the ground.
You may have a different model loader (I had a choice of three that would fit my tractor if I remember correctly) so your geometry may be different.
Howevr you do it, just make sure you can change your fork width. Mine spread to 4'6" or come tight enough to run one up each side of a skidoo track to lift them from the rear. In fact the forks will come right off the back frame so I can replace them with my 5' boom lift. This summer I hope to also mount a snowplow to the same frame....