NavList:

 A bit late ...

Venus 13:40:00 UT  Hs = 44°59.3' : Height correction -5.8', hence Ho = 44°53.5'

I did not perform parallax correction, neither temp correction, both being [well] under 1'.

With Venus Dec = -3°40.1' get approximate Latitude at N41°26.4' and "very approximate longitude" = Venus GHA  = W 071°07.8'

For the Sun at 13:40:35 UT get : GHA = 28°45.3' Dec = -19°42.4'

With SUN LL Hs 17°05' , get a correction of +8.2' hence Ho = 17°13.2' probably more sensitive to Temp because Refraction is higher. I did not correct for either temp, QNH or Departure from average SD.

As regards the Sun Ho, and from the well known Height Formula :

- We know Latitude (N41°26.4')

- We know Declination (-19°42.4')

- We know Ho (17°13.2')

So we can compute "T" (SUN LHA).

I am assuming this is where you are leading us to, non ?

Get cos SUN LHA = 0.735689 , hence LHA = 42°38.1' .

Longitude = SUN GHA + SUN LHA = 28°45.3' + 42°38.1' = W 071°23.4'

So Observer's approximate position is : N41°26.4' / W071°23.4'

Overkill method : (i.e. LOP's) 

Venus 13h40:00 Hs = 44°59.3' / Sun LL 13h40m35,0s Hs = 17°05.0'

With only this data (+ environmental data of course)

Get N41°26.4' / W 071°23.4' ...

Same position. 

Thanks for the drill

Kermit