I don't vouch for the following's accuracy. Years ago, I found a folder of all the Roman Missal's texts and chants codified into GABC, and I downloaded it. Don't remember where I got it. This is from that collection:

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\section*{\black{Credo III}}
\addcontentsline{toc}{section}{\black{Credo III}}
(c4) () I(g) be-(e)lieve(c) in(f) one(evDC) God,(c) (::) the(g) Fa-(g)ther(e) al-(c)might-(d)y,(c) (;) mak-(c)er(e) of(f) heav-(g)en(g) and(h) earth,(g) (;) of(j) all(igh) things(g) (;) vis-(g)i-(g)ble(e) and(c) in-(f)vis-(ecd)i-(d)ble.(c) (::) (Z) I(g) be-(g)lieve(e) in(e) one(c) Lord(f) Je-(ecd)sus(d) Christ,(c) (,) the(e) On-(e)ly(d) Be-(e)got-(g)ten(g) Son(h) of(h) God,(g) (::) born(ed) of(f) the(f) Fa-(ecd)ther(c) (,) be-(e)fore(gh) all(g) a-(ecd)ges.(c) (::) God(g) from(e) God,(c) (,) Light(de) from(d) Light,(c) (,) true(gh) God(g) from(j) true(igh) God,(g) (::) be-(g)got-(ec)ten,(d) not(d) made,(c) (,) con-(e)sub-(e)stan-(g)tial(g) with(h) the(g) Fa(f)ther;(g) (;) through(j) him(i) all(g) things(h) were(h) made.(g) (::) For(e) us(gh) men(g) (,) and(c) for(c) our(c) sal-(d)va-(ef)tion(g) (,) he(g) came(g) down(hi) from(j) heav-(igh)en,(g) (::)
At the words that follow, up to and including \black{and became man}, all bow.
(c4) () and(g) by(g) the(g) Ho-(e)ly(e) Spir-(cd)it(c) (,) was(ed) in-(e)car-(gh)nate(g) (,) of(g) the(g) Vir-(h)gin(j) Mar-(igh)y,(g) (;) and(c) be-(c)came(ef) man.(g) (::)
(c4) () For(e) our(e) sake(d) he(f) was(f) cru-(ecd)ci-(d)fied(c) (,) un-(c)der(d) Pon-(e)tius(f) Pi-(gh)late,(g) (,) he(g) suf-(h)fered(f) death(g) and(e) was(f) bur-(ecd)ied,(c) (::) and(g) rose(g) a-(g)gain(h) on(g) the(g) third(ef) day(g) (,) in(c) ac-(c)cor-(c)dance(d) with(e) the(f) Scrip-(d)tures.(c) (::) He(c) as-(e)cend-(g)ed(h) in-(i)to(j) heav-(igh)en(g) (;) and(e) is(e) seat-(g)ed(g) at(h) the(g) right(e) hand(e) of(d) the(f) Fa-(ecd)ther.(c) (::) He(g) will(g) come(e) a-(e)gain(c) in(d) glo-(ed)ry(c) (,) to(g) judge(hg) the(j) liv-(i)ing(g) and(h) the(h) dead(g) (;) and(g) his(g) king-(e)dom(c) will(f) have(ec) no(d) end.(c) (::)
(c4) () I(j) be-(j)lieve(h) in(h) the(j) Ho-(g)ly(g) Spir-(h)it,(g) (,) the(c) Lord,(e) the(e) giv-(g)er(g) of(h) life,(g) (;) who(g) pro-(e)ceeds(fd) from(e) the(f) Fa-(e)ther(c) and(d) the(d) Son,(c) (::) who(c) with(c) the(e) Fa-(g)ther(g) and(f) the(e) Son(g) (,) is(g) a-(g)dored(hg) and(j) glo-(igh)ri-(h)fied,(g) (;) who(g) has(g) spo-(e)ken(e) through(c) the(f) proph-(ecd)ets.(c) (::) I(g) be-(g)lieve(e) in(e) one,(f) ho-(e)ly,(c) ca-(d)tho-(d)lic(c) (,) and(g) a-(h)pos-(f)tol-(g)ic(g) Church.(e) (::) I(g) con-(g)fess(hi) one(j) Bap-(igh)tism(g) (,) for(g) the(e) for-(f)give-(ec)ness(d) of(d) sins(c) (::) and(g) I(g) look(g) for-(e)ward(e) to(c) the(c) res-(g)ur-(g)rec-(h)tion(g) of(f) the(f) dead(e) (::) and(j) the(j) life(ih) of(g) the(e) world(hvGE) to(f) come.(g) (::) A(gvECddcc//jvIGhhg//ef!gv/cddc)men.(c) (::)