Oh, definitely, way less solids. "Until one, it's just for fun." Meaning that babies' only real form of nourishment needs to be breastmilk or, failing that, of course, formula. Solids are not supposed to replace your breastmilk in growing your baby, only go in on top of it. The La Leche League leader I spoke with about solids amounts said that LLL recommends feeding solids only after nursing. This way, you ensure that solids are not in any way replacing the breastmilk intake.
I still cheat and give my daughter snacks between nursing sessions, when she has something of an appetite, but I don't make it more than about 1/8 of a cup per "meal," (that actually makes its way in ;) and this is only once or twice a day, absolute max. It seems to be working out well, and my milk supply hasn't diminished. Usually, in fact, I'll just give her a few tastes of what I'm eating (even better, since I don't have to pull out a bib, put stuff in a little cup, stick her in her high chair, etc. I'm holding her and I mash up some banana between my fingers, and she's happy).
Even if your daughter is happily eating 10 oz. or more per meal, don't just let her do what she likes best. She'd eat that much in sugar, too ;) What I mean is, we can't always follow their inclinations. And I think the ped was missing one thing. Don't just reduce to 3 meals of solids per day. (Even make it one or two per day. Three is a lot for an 8-month old.) Reduce the amount at every meal to just, well, something like 1/8 cup (I think in things I see, and oz. doesn't work for me). Because you'll be nursing her, first, she will feel well fed and she won't be too frustrated with this. If she seems to be, then distract, distract, distract. Take her out for a walk in this lovely spring weather! Show her that stroller/baby carrier and make a big deal of what a great thing you have in store for her as soon as you can whisk her out of that high chair. Leave the dishes in the sink and scram ;)
L.
PS about her being fussy, what are the circumstances? Times of day/night when she's fussiest? Any new behaviors coming along with it, like ear tugging or cheek rubbing? Maybe go into some more detail and post it, and we'll see what we can do for you, mama :)