Don't know what impact any position would make. As long as it is in a safe position and no one can be under the FEL or bucket.
I just did a 200 hour service and replaced hyd fluid also. The hoses will hold about a gallon or so. At least that is what I surmised.
( based on Capacity about 11.9 gallons, yet a full drain was only 10 gallons.)
What little is left over in the hoses should not be a big negative impact.
Typically a fluid change will also include fresh filters so that should really clean up well.