Zone 8 sounds like heat and sun both. My primary references are:

American Rhododendron Society

Greer Gardens, Eugene, Oregon

Rare Find Nursery, Jackson, NJ

None of these mention any special problem with sun exposure. Rcv. 'Elsie Frye' is very prone to rust and as a result is hard to find at better nurseries. Rust is best controlled by avoiding those hybrids and species which are very susceptible to rust. Good air circulation is helpful. Triadimefon seems to help, but may not be registered for use on rhododendrons.

I would check with your extension service on their recommendations for your area, wherever it is.

Given the number of cloudy days we have during the growing season, and our latitude, we can get away with much sunnier sites than many parts of the country. Close proximity to a large body of water will also put enough moisture in the air that your rhododendron can take more direct sun than in a drier atmosphere. But, you may find some sunscald until the shrub is well established and older, and the flowers may not last as long in a full sun site.

I'm wondering about the low end of the temps I'm finding for Elsie Frye.....15F. If you are on a hilly slope (Discovery Bay?) I think there is a chance you could have some winter damage from those occasional freezing E winter winds - not that you couldn't provide some protection during those brief periods.

Thanks so much - It seems that sun is not going to be so much of an issue, but we also get quite a bit of wind. I have to give it a try.

I've been looking at the online catalog of the Species Rhododendron Society and there seem to be an amazing number of sun tolerant Rhodies.

I've known and seen this plant in this area for decades. I have not picked up on the rust problem, but maybe it manifests as little more than scattered small speckles and patches - I may have seen that.

Anyway, I would not plant it in a hot spot where other kinds would be expected to have foliage damage or premature wilting of the flowers.